Question About UV Projections, Layered Shaders, And Trimmed Surfaces

I'm building a model of an aircraft in Maya, and I've created the wing by lofting (resulting in a NURBs object). I then projected curves onto the surface and trimmed it to create the ailerons and flaps. However, now I'm running into a strange situation. I want to apply a layered shader to the wing for a logo (think decal), however, every time I try to apply a projection to the trimmed surface it says its not a proper NURBs object and won't do it

Now I can create the projection in the shader, but this brings up a problem with not being able to align the file for the alpha channel with the original image.

Any thoughts on this would be very appreciated! Let me know if I'm not being clear enough in my description of the problem too.

Okay, I figured this one out. It's a "kludge," but it works. Take the file you want to make the "decal" out and duplicate it in Photoshop. Create what amounts to be an Alpha channel image in grayscale (white for what shows, black for what is transparent) and save the file. In the shader network, select the layer node. Select the approriate layer (the one linked to the original file) and link the alpha to a file node. This new file node will be the "alpha channel image" you just created in photoshop. Set your 3d and 2d projection nodes to match and turn the colors all the way to black and - viola - you have masked the original file.

The shader network looks horribly messy, but it works. Honestly, I'm hoping that someone will post a more elegant solution to this problem.

I'm sorry, I was rushed and probably didn't make much sense. I have a NURBs surface (lofted), which was then trimmed (by projecting a curve onto the surface and trimming). I then attempted to apply a UV projection do it and I received a error message in the MEL. Something to the extent of not being able to do this to a trimmed surface. It suggested converting the surface to a polygon, but when I tried that it failed.

In the end I create a layered shader for the object and selected a projection (when adding the layered shader - as opposed to normal). Once that was set where I wanted it, I added a separate mask file to the Alpha channel of the particular layer within the layered shader. I then applied the appropriate positioning information to fit it behind the original layered image and viola, it worked.

However, this strikes me as very in-elegant. I've got to believe there is a simpler way of doing this.